Spinal disc annulus reconstruction method and spinal disc annulus stent

ABSTRACT

A surgical method of repair and reconstruction of the spinal disc wall (annulus) after surgical invasion or pathologic rupture, incorporating suture closure, or stent insertion and fixation, designed to reduce the failure rate of conventional surgical procedures on the spinal discs.  
     The design of the spinal disc annulus stent allows ingrowth of normal cells of healing in an enhanced fashion strengthening the normal reparative process.

CROSS-REFERENCE TO A RELATED APPLICATION

[0001] This application is a continuation of co-pending U.S. Ser. No.09/947,078, filed Sep. 5, 2001; which is a continuation of U. S. Ser.No. 09/484,706, filed Jan. 18, 2000 (now abandoned); which claims thebenefit of U.S. Provisional Application No. 60/160,710, filed Oct. 20,1999.

FIELD OF THE INVENTION

[0002] The invention generally relates to a surgical method ofintervertebral disc wall reconstruction with a related annulus stentaugmenting the repair. The effects of said reconstruction arerestoration of disc wall integrity and reduction of the failure rate(3-21%) of a common surgical procedure (disc fragment removal ordiscectomy). This surgical procedure is performed about 390,000 timesannually in the United States.

BACKGROUND OF THE INVENTION

[0003] The spinal column is formed from a number of vertebrae, which intheir normal state are separated from each other by cartilaginousintervertebral discs. The intervertebral disc acts in the spine as acrucial stabilizer, and as a mechanism for force distribution betweenthe vertebral bodies. Without the disc, collapse of the intervertebralspace occurs in conjunction with abnormal joint mechanics and prematuredevelopment of arthritic changes.

[0004] The normal intervertebral disc has an outer ligamentous ringcalled the annulus surrounding the nucleus pulposus. The annulus bindsthe adjacent vertebrae together and is constituted of collagen fibersthat are attached to the vertebrae and cross each other so that half ofthe individual fibers will tighten as the vertebrae are rotated ineither direction, thus resisting twisting or torsional motion. Thenucleus pulposus is constituted of loose tissue, having about 85% watercontent, which moves about during bending from front to back and fromside to side.

[0005] As people age, the annulus tends to thicken, desicate, and becomemore rigid. The nucleus pulposus, in turn, becomes more viscous and lessfluid and sometimes even dehydrates and contracts. The annulus alsobecomes susceptible to fracturing or fissuring. These fractures tend tooccur all around the circumference of the annulus and can extend fromboth the outside of the annulus inwards, and the interior outward.Occasionally, a fissure from the outside of the annulus meets a fissurefrom the inside and results in a complete rent or tear through theannulus fibrosis. In situations like these, the nucleus pulposus mayextrude out through the annulus wall. The extruded material, in turn,can impinge on the spinal cord or on the spinal nerve rootlet as itexits through the intervertebral disc foramen, resulting in a conditiontermed ruptured disc or herniated disc

[0006] In the event of annulus rupture, the inner-nucleus componentmigrates along the path of least resistance forcing the fissure to openfurther, allowing migration of the nucleus pulposus through the wall ofthe disc, with resultant nerve compression and leakage of chemicals ofinflammation into the space around the adjacent nerve roots supplyingthe extremities, bladder, bowel and genitalia. The usual effect of nervecompression and inflammation is intolerable back or neck pain, radiatinginto the extremities, with accompanying numbness, weakness, and in latestages, paralysis and muscle atrophy, and/or bladder and bowelincontinence. Additionally, injury, disease or other degenerativedisorders may cause one or more of the intervertebral discs to shrink,collapse, deteriorate or become displaced, herniated, or otherwisedamaged.

[0007] The surgical standard of care for treatment of herniated,displaced or ruptured intervertebral discs is fragment removal and nervedecompression without a requirement to reconstruct the annular wall.While results are currently acceptable, they are not optimal. Variousauthors report 3.1-21% recurrent disc herniation, representing a failureof the primary procedure and requiring re-operation for the samecondition. An estimated 10% recurrence rate results in 39,000re-operations in the United States each year.

[0008] An additional method of relieving the symptoms is thermalannuloplasty, involving the heating of sub-annular zones in thenon-herniated painful disc, seeking pain relief, but making no claim ofreconstruction of the ruptured, discontinuous annulus wall.

[0009] There is currently no known method of annulus reconstruction,either primarily or augmented with an annulus stent.

BRIEF SUMMARY OF THE INVENTION

[0010] The present invention provides methods and related materials forreconstruction of the disk wall in cases of displaced, herniated,ruptured, or otherwise damaged intervertebral discs.

[0011] In a preferred form, one or more mild biodegradable surgicalsutures are placed at about equal distances along the sides of apathologic aperture in the ruptured disc wall (annulus) or along thesides of a surgical incision in the weakened, thinned disc annulus.

[0012] Sutures are then tied in such fashion as to draw together thesides of the aperture, effecting reapproximation or closure of theopening, to enhance natural healing and subsequent reconstruction bynatural tissue (fibroblasts) crossing the now surgically narrowed gap inthe disc annulus.

[0013] A 25-30% reduction in the rate of recurrence of disc nucleusherniation through this aperture, has been achieved using this method.

[0014] In another embodiment, the method can be augmented by placementof a patch of human muscle fascia (the membrane covering the muscle) orany other autograft or allograft acting as a bridge in and across theaperture, providing a platform for traverse of fibroblasts or othernormal cells of repair existing in and around the various layers of thedisc annulus, prior to closure of the aperture.

[0015] A 30-50% reduction in the rate of recurrence of disc herniationhas been achieved using the aforementioned fascial augmentation withthis embodiment.

[0016] Having demonstrated that human muscle fascia is adaptable forannular reconstruction, other biocompatible membranes can be employed asa bridge, stent, patch or barrier to subsequent migration of the discnucleus through the aperture. Such biocompatible materials may be, forexample, a medical grade biocompatible fabric, biodegradable polymericsheets, or form fitting or non-form fitting fillers for the cavitycreated by removal of a portion of the disc nucleus in the course of thedisc fragment removal or discectomy. The prosthetic material can beplaced in and around the intervertebral space, created by removal of thedegenerated disc fragments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 shows a perspective view of the annulus stent.

[0018]FIG. 2 shows a front view of the annulus stent.

[0019]FIG. 3 shows a side view of the annulus stent.

[0020] FIGS. 4A-4C show a front view of various alternative embodimentsof the annulus stent.

[0021] FIGS. 5A-5B shows the alternative embodiment of a pyramid shapedannulus stent.

[0022] FIGS. 6A-6B shows the alternative embodiment of a coned shapedannulus stent.

[0023]FIG. 7 shows the primary closure of the opening in the discannulus, without an intervertebral or subannular stent.

[0024] FIGS. 8A-8B shows the primary closure with a stent in genericform.

[0025]FIG. 9 shows a method of suturing the annulus stent into the discannulus, utilizing sub-annular fixation points.

[0026] FIGS. 10A-10B show the annulus stent with flexible bladder beingexpanded into the disc annulus.

[0027] FIGS. 11A-11D show the annulus stent being inserted into the discannulus.

[0028] FIGS. 12A-12B show the annulus stent with the flexible bladderbeing expanded by injection.

DETAILED DESCRIPTION OF THE INVENTION

[0029] The present invention provides methods and related materials forreconstruction of the disk wall in cases of displaced, herniated,ruptured, or otherwise damaged intervertebral discs.

[0030] In one embodiment of the present invention, as shown in FIG. 7, adamaged annulus 42 is repaired by use of surgical sutures 40. One ormore surgical sutures 40 are placed at about equal distances along thesides of a pathologic aperture 44 in the ruptured annulus 42.Reapproximation or closure of the aperture 44 is accomplished by tyingthe sutures 40 in such a fashion that the sides of the aperture 44 aredrawn together. The reapproximation or closure of the aperture 44enhances the natural healing and subsequent reconstruction by thenatural tissue crossing the now surgically narrowed gap in the annulus42. Preferably, the surgical sutures 40 are biodegradable, but permanentnon-biodegradable may be utilized.

[0031] Additionally, to repair a weakened or thinned disc annulus 42, asurgical incision is made along the weakened or thinned region of theannulus 42 and one or more surgical sutures 40 are placed at about equaldistances along the sides of the incision. Reapproximation or closure ofthe incision is accomplished by tying the sutures 40 in such a fashionthat the sides of the incision are drawn together. The reapproximationor closure of the incision enhances the natural healing and subsequentreconstruction by the natural tissue crossing the now surgicallynarrowed gap in the annulus 42. Preferably, the surgical sutures 40 arebiodegradable, but permanent non-biodegradable materials may beutilized.

[0032] In an alternative embodiment, the method can be augmented by theplacement of a patch of human muscle fascia or any other autograft,allograft or xenograft in and across the aperture 44. The patch acts asa bridge in and across the aperture, providing a platform for traverseof fibroblasts or other normal cells of repair existing in and aroundthe various layers of the disc annulus, prior to closure of theaperture.

[0033] In a further embodiment, as shown in FIG. 8, a biocompatiblemembrane can be employed as an annulus stent 10, being placed in andacross the aperture 44. The annulus stent 10 acts as a bridge in andacross the aperture 44, providing a platform for a traverse offibroblasts or other normal cells of repair existing in and around thevarious layers of the disc annulus, prior to closure of the aperture 44.

[0034] In a preferred embodiment, as shown in FIGS. 1-3, the annulusstent 10 comprises a centralized vertical extension 12, with an uppersection 14 and a lower section 16. The centralized vertical extension 12can be trapezoid in shape through the width and may be from about 8mm-12 mm in length.

[0035] Additionally, the upper section 14 of the centralized verticalextension 12 may be any number of different shapes, as shown in FIGS. 4Aand 4B, with the sides of the upper section 14 being curved or with theupper section 14 being circular in shape. Furthermore, the annulus stent10 may contain a recess between the upper section 14 and the lowersection 16, enabling the annulus stent 10 to form a compatible fit withthe edges of the aperture 44.

[0036] The upper section 14 of the centralized vertical extension 12 cancomprise a slot 18, where the slot 18 forms an orifice through the uppersection 14. The slot 18 is positioned within the upper section such that14 it traverses the upper section's 14 longitudinal axis. The slot 18 isof such a size and shape that sutures, tension bands, staples or anyother type of fixation device known in the art may be passed through, toaffix the annulus stent 10 to the disc annulus 44.

[0037] In an alternative embodiment, the upper section 14 of thecentralized vertical extension 12 may be perforated. The perforatedupper section 14 contains a plurality of holes which traverse the uppersection's 14 longitudinal axis. The perforations are of such a size andshape that sutures, tension bands, staples or any other type of fixationdevice known in the art may be passed through, to affix the annulusstent 10 to the disc annulus 44.

[0038] The lower section 16 can comprise a pair of lateral extensions, aleft lateral extension 20 and a right lateral extension 22. The lateralextensions 20 and 22 comprise an inside edge 24, an outside edge 26, anupper surface 28, and a lower surface 30. The lateral extensions 20 and22 can have an essentially constant thickness throughout. The insideedge 24 is attached to the lower section 16 and is about the same lengthas the lower section 16. The outside edge 26 can be about 8 mm-16 mm inlength. The inside edge 24 and the lower section 16 meet to form ahorizontal plane, essentially perpendicular to the centralized verticalextension 12. The upper surface 28 of the lateral extensions 20 and 22can form an angle of about 0°-60° below the horizontal plane. The widthof the annulus stent 10 may be from about 3 mm-5 mm.

[0039] Additionally, the upper surface 28 of the lateral extensions 20and 22 may be barbed for fixation to the inside surface of the discannulus 40 and to resist expulsion through the aperture 44.

[0040] In an alternative embodiment, as shown in FIG. 4B, the lateralextensions 20 and 22 have a greater thickness at the inside edge 24 thanat the outside edge 26.

[0041] In a preferred embodiment, the annulus stent 10 is a solid unit,formed from one or more of the flexible resilient biocompatible orbioresorbable materials well know in the art.

[0042] For example, the annulus stent may be made from:

[0043] a porous matrix or mesh of biocompatible and bioresorbable fibersacting as a scaffold to regenerate disc tissue and replace annulusfibrosus as disclosed in, for example, U.S. Pat. No. 5,108,438 (Stone)and U.S. Pat. No. 5,258,043 (Stone);

[0044] a strong network of inert fibers intermingled with abioresorbable (or biosabsorable) material which attracts tissue ingrowthas disclosed in, for example, U.S. Pat. No. 4,904,260 (Ray et al.);

[0045] a biodegradable substrate as disclosed in, for example, U.S. Pat.No. 5,964,807 (Gan at al.); or

[0046] a expandable polytetrafluoroethylene (ePTFE), as used forconventional vascular grafts, such as those sold by W.L. Gore andAssociates, Inc. under the trademarks GORE-TEX and PRECLUDE, or byImpra, Inc. under the trademark IMPRA.

[0047] Furthermore, the annulus stent 10, may contain hygroscopicmaterial for a controlled limited expansion of the annulus stent 10 tofill the evacuated disc space cavity.

[0048] Additionally, the annulus stent 10 may comprise materials tofacilitate regeneration of disc tissue, such as bioactive silica-basedmaterials which assist in regeneration of disc tissue as disclosed inU.S. Pat. No. 5,849,331 (Ducheyne, et al.), or other tissue growthfactors well known in the art.

[0049] In further embodiments, as shown in FIGS. 5-6, the left and rightlateral extensions 20 and 22 join to form a solid pyramid or cone.Additionally, the left and right lateral extensions 20 and 22 may form asolid trapezoid, wedge, or bullet shape. The solid formation may be asolid biocompatible or bioresorbable flexible material, allowing thelateral extensions 20 and 22 to be compressed for insertion intoaperture 44, then to expand conforming to the shape of the annulus' 42inner wall.

[0050] Alternatively, a compressible core may be attached to the lowersurface 30 of the lateral extensions 20 and 22, forming a pyramid, cone,trapezoid, wedge, or bullet shape. The compressible core may be madefrom one of the biocompatible or bioresorbable resilient foams wellknown in the art. The compressible core allows the lateral extensions 20and 22 to be compressed for insertion into aperture 44, then to expandconforming to the shape of the annulus' 42 inner wall and to the cavitycreated by pathologic extrusion or surgical removal of the discfragment.

[0051] In a preferred method of use, as shown in FIGS. 10A-10D, thelateral extensions 20 and 22 are compressed together for insertion intothe aperture 44 of the disc annulus 40. The annulus stent 10 is theninserted into the aperture 44, where the lateral extensions 20 and 22expand, with the upper surface 28 contouring to the inside surface ofthe disc annulus 40. The upper section 14 is positioned within theaperture 44 so that the annulus stent 10 may be secured to the discannulus 40, using means well known in the art.

[0052] In an alternative method, where the length of the aperture 44 isless than the length of the outside edge 26 of the annulus stent 10, theannulus stent 10 must be inserted laterally into the aperture 44. Thelateral extensions 20 and 22 are compressed, and the annulus stent 10 islaterally inserted into the aperture 44. The annulus stent 10 is thenrotated inside the disc annulus 40, such that the upper section 14 ispulled back through the aperture 44. The lateral extensions 20 and 22are then allowed to expand, with the upper surface 28 contouring to theinside surface of the disc annulus 40. The upper section 14 ispositioned within the aperture 44 such that the annulus stent 10 may besecured to the disc annulus, using means well known in the art.

[0053] In an alternative method of securing the annulus stent 10 in theaperture 44, as shown in FIG. 9, a first surgical screw 50 and secondsurgical screw 52, with eye holes 53 located at the top of the screws 50and 52, are opposingly inserted into the adjacent vertebrae 54 and 56below the annulus stent 10. After insertion of the annulus stent 10 intothe aperture 44, a suture is passed down though the disc annulus 40,adjacent to the aperture 44, through the eye hole 53 on the first screw50 then back up through the disc annulus 40 and through the orifice 18on the annulus stent 10. This is repeated for the second screw 52, afterwhich the suture is secured. One or more surgical sutures 40 are placedat about equal distances along the sides of the aperture 44 in the discannulus 42. Reapproximation or closure of the aperture 44 isaccomplished by tying the sutures 40 in such a fashion that the sides ofthe aperture 44 are drawn together. The reapproximation or closure ofthe aperture 44 enhances the natural healing and subsequentreconstruction by the natural tissue crossing the now surgicallynarrowed gap in the annulus 42. Preferably, the surgical sutures 40 arebiodegradable but permanent nonbiodegradable forms may be utilized. Thismethod should decrease the strain on the disc annulus 40 adjacent to theaperture 44, precluding the tearing of the sutures through the discannulus 40.

[0054] It is anticipated that fibroblasts will engage the fibers of thepolymer or fabric of the intervertebral disc stent, forming a strongwall duplicating the currently existing condition of healing seen in thenormal reparative process.

[0055] In an additional embodiment, as shown in FIGS. 10A-B, a flexiblebladder 60 is attached to the lower surface 30 of the annulus stent 10.The flexible bladder 60 comprises an internal cavity 62 surrounded by amembrane 64, where the membrane 64 is made from a thin flexiblebiocompatible material. The flexible bladder 60 is attached to the lowersurface 28 of the annulus stent 10 in an unexpanded condition. Theflexible bladder 60 is expanded by injecting a biocompatible fluid orexpansive foam, as known in the art, into the internal cavity 62. Theexact size of the flexible bladder 60 can be varied for differentindividuals. The typical size of an adult nucleus is 2 cm in thesemi-minor axis, 4 cm in the semi-major axis and 1.2 cm in thickness.

[0056] In an alternative embodiment, the membrane 64 is made of asemipermeable biocompatible material.

[0057] In a preferred embodiment, a hydrogel is injected into theinternal cavity of the flexible bladder 28. A hydrogel is a substanceformed when an organic polymer (natural or synthetic) is cross-linkedvia covalent, ionic, or hydrogen bonds to create a three-dimensionalopen-lattice structure which entraps water molecules to form a gel. Thehydrogel may be used in either the hydrated or dehydrated form.

[0058] In a method of use, where the annulus stent 10 has been insertedinto the aperture, as has been previously described and shown in FIGS.12 A-b, an injection instrument, as known in the art, such as a syringe,is used to inject the biocompatible fluid or expansive foam into theinternal cavity 62 of the flexible bladder 60. The biocompatible fluidor expansive foam is injected through the annulus stent 10 into theinternal cavity of the flexible bladder 28. Sufficient material isinjected into the internal cavity 62 to expand the flexible bladder 60to fill the void in the intervertebral disc cavity. The use of theflexible bladder 60 is particularly useful when it is required to removeall or part of the intervertebral disc nucleus.

[0059] The surgical repair of an intervertebral disc may require theremoval of the entire disc nucleus, being replaced with an implant, orthe removal of a portion of the disc nucleus thereby leaving a void inthe intervertebral disc cavity. The flexible bladder 60 allows for theremoval of only the damaged section of the disc nucleus, with theexpanded flexible bladder 60 filling the resultant void in theintervertebral disc cavity. A major advantage of the annulus stent 10with the flexible bladder 60 is that the incision area in the annuluscan be reduced in size as there is no need for the insertion of animplant into the intervertebral disc cavity.

[0060] In an alternative method of use, a dehydrated hydrogel isinjected into the internal cavity 28 of the flexible bladder 60. Fluid,from the disc nucleus, passes through the semi-permeable membrane 64hydrating the dehydrated hydrogel. As the hydrogel absorbs the fluid theflexible bladder expands 60, filling the void in the intervertebral disccavity.

[0061] All patents referred to or cited herein are incorporated byreference in their entirety to the extent they are not inconsistent withthe explicit teachings of this specification, including; U.S. Pat. No.5,108,438 (Stone), U.S. Pat. No. 5,258,043 (Stone), U.S. Pat. No.4,904,260 (Ray et al.), U.S. Pat. No. 5,964,807 (Gan et al.), U.S. Pat.No. 5,849,331 (Ducheyne et al.), U.S. Pat. No. 5,122,154 (Rhodes), U.S.Pat. No. 5,204,106 (Schepers at al.), U.S. Pat. No. 5,888,220 (Felt etal.) and U.S. Pat. No. 5,376,120 (Sarver et al.).

[0062] It should be understood that the examples and embodimentsdescribed herein are for illustrative purposes only and that variousmodifications or changes in light thereof will be suggested to personsskilled in the art and are to be included within the spirit and previewof this application and the scope of the appended claims.

1. An annulus stent, for repair of an intervertebral disc annulus,comprising an elongated centralized vertical extension, said centralizedvertical extension comprising a left and a right lateral extension alongsaid centralized vertical extension's horizontal axis.
 2. The annulusstent according to claim 1, wherein said vertical extension furthercomprises a slot.
 3. The annulus stent according to claim 1, whereinsaid vertical extension is perforated.
 4. The annulus stent according toclaim 1, wherein said left and right lateral extensions comprise aninside edge, an outside edge, an upper surface and a lower surface,wherein said inside edge joins said centralized vertical extension toform a horizontal plane.
 5. The annulus stent according to claim 4,wherein said upper surface forms an angle of about 0 to 60 degrees belowsaid horizontal plane.
 6. The annulus stent according to claim 4,wherein the length of said inside edge is less than the length of saidoutside edge.
 7. The annulus stent according to claim 4, wherein saidinside edge has a greater thickness than said outside edge.
 8. Theannulus stent according to claim 4, wherein said upper surface isbarbed.
 9. The annulus stent according to claim 4, further comprising arecess wherein said upper surface joins said centralized verticalextension.
 10. The annulus stent according to claim 4, wherein saidlateral extension further comprises a compressible core affixed to saidlower surface.
 11. The annulus stent according to claim 10, wherein saidcompressible core is made of a compressible biocompatible material. 12.The annulus stent according to claim 10, wherein said compressible coreis made of a compressible bioreabsorbable material.
 13. The annulusstent according to claim 4, further comprising a flexible bladderaffixed to said lower surface of said left and right lateral extensions.14. The annulus stent according to claim 13, wherein said flexiblebladder comprises a membrane enclosing an internal cavity.
 15. Theannulus stent according to claim 14, wherein said internal cavity isempty.
 16. The annulus stent according to claim 14, wherein saidmembrane comprises a thin flexible biocompatible material.
 17. Theannulus stent according to claim 16, wherein said membrane furthercomprises a semi-permeable material.
 18. The annulus stent according toclaim 17, wherein said internal cavity contains a biocompatible fluid.19. The annulus stent according to claim 18, wherein said biocompatiblefluid is a hydrogel.
 20. The annulus stent according to claim 16,wherein said membrane further comprises an impermeable material.
 21. Theannulus stent according to claim 20, wherein said internal cavitycontains a biocompatible fluid.
 22. The annulus stent according to claim1, wherein said centralized vertical extension is of a shape selectedfrom the group consisting of a trapezoid, circular and curved.
 23. Theannulus stent according to claim 1, wherein said annulus stent is madefrom a material selected from the group consisting of a biocompatiblematerial, a bioactive material, and a bioreabsorbable material.
 24. Theannulus stent according to claim 23, wherein said annulus stent is madefrom a biocompatible fiber mesh.
 25. The annulus stent according toclaim 23, wherein said annulus stent is made from a bioreabsorbablefiber mesh.
 26. The annulus stent according to claim 23, wherein saidannulus stent is made from expandable polytetra fluoroethylyene.
 27. Theannulus stent according to claim 1, wherein said annulus stent comprisesa material to facilitate regeneration of disc tissue.
 28. The annulusstent according to claim 1, wherein said annulus stent comprises ahygroscopic material.
 29. An annulus patch, wherein said annulus patchis of the size and shape for repair of a intervertebral disc annulus.30. The annulus patch according to claim 29, wherein said annulus patchis human muscle fascia, an autograft, an allograft or a xenograft.
 31. Amethod for repairing an intervertebral disc, wherein said intervertebraldisc comprises a disc nucleus and a disc annulus, comprising the stepsof; a) forming an aperture in said intervertebral disc annulus; and b)securing across said aperture to said intervertebral disc annulus anannulus patch.
 32. The method for repairing an intervertebral discaccording to claim 31, wherein said annulus patch is human musclefascia, an autograft, an allograft, or a xenograft.
 33. The method forrepairing an intervertebral disc according to claim 31, furthercomprising the step of preparing said intervertebral disc, wherein saidpreparation step comprises the steps; a) identifying a damaged sectionof said disc nucleus; and b) removing said damaged section of said discnucleus.
 34. A method for repairing an intervertebral disc, wherein saidintervertebral disc comprises a disc nucleus and a disc annulus,comprising the steps of; a) forming an aperture in said intervertebraldisc annulus; b) inserting an annulus stent into said aperture, whereinsaid annulus stent comprises an elongated centralized verticalextension, a left and a right lateral extension along said centralizedvertical extension's horizontal axis; and c) securing said annulus stentto said intervertebral disc annulus.
 35. The method for repairing anintervertebral disc according to claim 34, wherein said step of formingsaid aperture in said disc annulus comprises the step of making asurgical incision into said disc annulus.
 36. The method for repairingan intervertebral disc according to claim 34, wherein said step ofinserting said annulus stent into said aperture comprises the steps of;a) compressing said left and right lateral extensions together; b)inserting said annulus stent into said aperture, such that an uppersurface of said left and right lateral extensions conforms to an insidesurface of said disc annulus; and c) positioning said centralizedvertical extension within said aperture, such that said annulus stentmay be secured to said disc annulus.
 37. The method for repairing anintervertebral disc according to claim 34, wherein said step ofinserting said annulus stent into said aperture comprises the steps of;a) compressing said left and right lateral extension together; b)rotating said annulus stent, such that said annulus stent may belaterally inserted into said intervertebral disc; c) inserting saidannulus stent laterally through said aperture into said intervertebraldisc; d) rotating said annulus stent within said intervertebral disc,such that an upper surface of said left and right lateral extensionsconforms to an inside surface of said disc annulus; and e) positioningsaid centralized vertical extension within said aperture, such that saidannulus stent may be secured to said disc annulus.
 38. The method forrepairing an intervertebral disc according to claim 34, furthercomprising a step of preparing said intervertebral disc, wherein saidpreparation step comprises the steps of inserting a set surgical screwsinto a pair of adjacent intervertebral, wherein said surgical screwscomprise an eye hole located at the top of said surgical screw.
 39. Themethod for repairing an intervertebral disc according to claim 38,wherein said step of securing said annulus stent to said intervertebraldisc comprises the steps of threading a surgical suture through said eyehole on said surgical screw.
 40. The method for repairing anintervertebral disc according to claim 34, further comprising the stepof preparing said intervertebral disc, wherein said preparation stepcomprises the steps; a) identifying a damaged section of said discnucleus; and b) removing said damaged section of said disc nucleus. 41.The method for repairing an intervertebral disc according to claim 40,wherein said step of inserting said annulus stent into said aperturecomprises the steps of; a) compressing said left and right lateralextensions together; b) inserting said annulus stent into said aperture,such that an upper surface of said left and right lateral extensionsconforms to an inside surface of said disc annulus; c) positioning saidcentralized vertical extension within said aperture, such that saidannulus stent may be secured to disc annulus; and d) injecting abiocompatible fluid into said internal cavity, through said annulusstent.
 42. The method for repairing an intervertebral disc according toclaim 41, wherein said biocompatible fluid comprises a hygroscopicmaterial.
 43. The method for repairing an intervertebral disc accordingto claim 40, wherein said step inserting said annulus stent into saidaperture comprises the steps of; a) compressing said left and rightlateral extensions together; b) rotating said annulus stent, such thatsaid annulus stent may be laterally inserted into said intervertebraldisc; c) inserting said annulus stent laterally through said apertureinto said intervertebral disc; d) rotating said annulus stent withinsaid intervertebral disc, such that an upper surface of said left andright lateral extensions conforms to an inside surface of said discannulus; e) positioning said centralized vertical extension within saidaperture, such that said annulus stent may be secured to disc annulus;and f) inject a biocompatible fluid into said internal cavity, throughsaid annulus stent.
 44. The method for repairing an intervertebral discaccording to claim 43, wherein said biocompatible fluid comprises ahygroscopic material.